1. Field of the Invention
This invention relates to a camera having a shutter driving device which, upon receipt of electric energy, drives shutter blades to open, and more particularly to a camera which is arranged to vary the amount of electric energy supplied to the shutter driving device.
2. Description of the Prior Art
There are various known shutter devices including lens shutters or shutters of the kind arranged to function also as a stop. The shutter devices of this kind further include shutter devices of the type having a so-called low-speed half-opening region in which the shutter blades are arranged to open at a relatively low speed.
Generally, the shutter device of this type is arranged to include a mechanical governor in a shutter blade opening device for driving the shutter blades at a given speed and thus to stabilizing the quantity of light incident on an image plane. In actuality, however, the opening speed of the shutter varies with the posture of the camera and environmental conditions, such as ambient temperature, humidity, etc. Therefore, it has been difficult to ensure an apposite quantity of light on the image plane.
Meanwhile, Japanese Laid-Open Patent Application No. SHO 55-96925 discloses a camera which is arranged to change the opening speed of the shutter in such a way as to have the so-called program curve changeable according to the object to be photographed and photographing conditions. However, in this arrangement the opening speed of the shutter still varies with the environmental conditions such as the ambient temperature, etc. It has been hardly possible, therefore, to adequately change the program curve with such arrangement.